Liberators' Civil War

The Liberators' Civil War was the second round of the Roman civil wars of 49-30 BC, fought between Julius Caesar's supporters Mark Antony and Octavian and his murderers, the Liberatores, led by Marcus Junius Brutus and Gaius Cassius Longinus. The war resulted in the victory of the Second Triumvirate, which came to rule over a Rome divided into thirds.

War
Julius Caesar’s death in 44 BC opened a new round of civil strife. Marcus Junius Brutus and Gaius Cassius Longinus ﬂed Rome and power was assumed by a Second Triumvirate: Mark Antony, an experienced ofﬁcer who had served under Caesar in Gaul as well as in the civil war; Caesar’s chosen heir, Octavian, an inexperienced boy of 19; and Marcus Aemilius Lepidus, a cavalry commander. They did not control the eastern provinces from Greece to Syria, however, which remained in the hands of the Republican forces. Brutus and Cassius took up a strong defensive position near Philippi in eastern Macedonia, where they confronted an army of similar size - probably around 100,000 men - led by Antony and Octavian. Two battles were fought at Philippi in October 42 BCE. In the ﬁrst Brutus’s forces overran Octavian’s camp in a surprise assault that found the young triumvir absent from his post. At the same time, Antony successfully attacked Cassius’s fortiﬁed position. Wrongly believing Brutus also to have been defeated, Cassius fell upon his sword. The Republicans were not defeated, but their morale was wavering and after a three-week stand-off Brutus felt obliged to give battle again. Rival legions clashed in a vicious close-quarters ﬁght that Octavian and Antony won. Left with inadequate forces to continue the war, Brutus too committed suicide.

Aftermath
After this victory Octavian returned to govern in Rome while Antony campaigned in the east. Both met with serious challenges. Sextus Pompey, a son of Pompey the Great, had seized Sicily, deploying a war ﬂeet to hold off Octavian’s legions. Octavian tasked his general, Marcus Vipsanius Agrippa, with building and equipping a ﬂeet to take on Sextus Pompeius. Agrippa destroyed most of the rebel warships at Naulochus in 36 BCE, allowing Octavian to retake Sicily. Meanwhile, Antony undertook an overambitious invasion of Parthia, successor power to the Seleucids in the East, losing large numbers of troops in the process. Starved of reinforcements by Octavian, he fell back on the support of Cleopatra of Egypt, establishing himself with her in Alexandria. Not long after, Antony's Civil War broke out, the last round of the conflict.